1628730457 has 4 divisors (see below), whose sum is σ = 1629416320. Its totient is φ = 1628044596.

The previous prime is 1628730449. The next prime is 1628730461. The reversal of 1628730457 is 7540378261.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 7540378261 = 13 ⋅580029097.

It is a cyclic number.

It is not a de Polignac number, because 1628730457 - 2³ = 1628730449 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1628730427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 339357 + ... + 344122.

It is an arithmetic number, because the mean of its divisors is an integer number (407354080).

Almost surely, 2^1628730457 is an apocalyptic number.

It is an amenable number.

1628730457 is a deficient number, since it is larger than the sum of its proper divisors (685863).

1628730457 is an equidigital number, since it uses as much as digits as its factorization.

1628730457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 685862.

The product of its (nonzero) digits is 282240, while the sum is 43.

The square root of 1628730457 is about 40357.5328408465. The cubic root of 1628730457 is about 1176.5663027637.

The spelling of 1628730457 in words is "one billion, six hundred twenty-eight million, seven hundred thirty thousand, four hundred fifty-seven".